Display device and vehicle

ABSTRACT

A vehicle has a display device which widens the field of view (visible area) reflected by a side mirror or a back mirror mounted on the vehicle. To enable a driver driving the vehicle to confirm safety even when it is difficult for the driver to visually recognize some of objects surrounding the vehicle, a liquid crystal display device or an EL display device is provided in the side mirror (door mirror), the back mirror (room mirror) or in an interior portion of the vehicle. A camera is mounted on the vehicle and an image from the camera is displayed on the display device. Further, information read from a sensor (distance measuring sensor) having the function of measuring the distance to another vehicle, and a sensor (impact sensor) having the function of sensing an externally applied impact force larger than a predetermined value is displayed on the display device.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to the structure and functionsof vehicles for conveyance of people and goods, for towing of cars forconveyance of such objects, and for other special purposes. Moreparticularly, the present invention relates to the structure andfunctions of side and back mirrors mounted on a vehicle.

2. Description of the Related Art

The term “vehicle” used in this specification refers to an electrictrain, a motor vehicle (e.g. car), or the like. Popularization ofvehicles typified by motor vehicles is progressing because of theirconvenience.

A vehicle is provided with a side mirror (door mirror) and a back mirror(room mirror), which are used by a driver to confirm safety at the timeof lane change, for example.

In this specification, “side mirror (door mirror)” refers to a mirrormounted on each side of the body of a vehicle to provide a driver with arear view, and “back mirror (room mirror)” refers to a mirror which ismounted in or adjacent to a space containing the driver's seat toprovide a driver with a rear view, and which is called a rearviewmirror.

When a driver driving a vehicle on a road makes a lane change, it isdifficult for the driver to perform necessary visual safety confirmationsince the driver is in the forward-facing driving position. It is alsodifficult for the driver to visually perform safety confirmation whenbacking the vehicle into a carport since a place at the rear of thevehicle is in the driver's blind spot. In such situations, the driverdrives the vehicle by relying on information obtained from scenesreflected by the side and back mirrors. However, the field of view(visible area) through each of the side and back mirrors is notsufficiently wide.

Under the above-described circumstances, the present invention aims towiden the fields of view through side and back mirrors.

It is important that a driver driving a vehicle on a road shouldrecognize the distance to another vehicle in any direction to avoid anaccident. However, drivers usually speed excessively when driving in thenight. Further, drivers tend to speed excessively after moving from ahighway to an ordinary road because of the influence of a sensation ofhigh speed in driving on the highway. Traffic accidents occur frequentlyin such situations, because drivers do not always correctly recognizethe vehicle speed and the distance to another vehicle in any direction.

Therefore, it is desirable that a driver who drives a vehicle and afellow passenger be able to obtain necessary information such as thedistance to another vehicle at any time.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above-describedcircumstances, and an object of the present invention is to provide avehicle having a camera and a sensor for enabling each of a driver whodrives the vehicle and the fellow passengers to obtain necessaryinformation.

Another object of the present invention is to provide a display devicecapable of displaying information read from a camera and a sensor, and avehicle having such a display device.

According to the present invention, to enable a driver driving thevehicle to confirm safety even when it is difficult for the driver tovisually recognize some of objects surrounding the vehicle, a liquidcrystal display device or an EL display device is provided in a sidemirror (door mirror), a back mirror (room mirror) or in an interiorportion of the vehicle. In this specification, the liquid crystaldisplay device and the EL display device will be collectively called“display device”. Further, to enable the driver and a fellow passengerin the vehicle to obtain necessary information at any time, the vehicleis provided with a camera, a distance measuring sensor and an impactsensor and information obtained from the camera or each sensor isdisplayed on the display device.

The camera is provided on the vehicle at a position selected as desired,and an image obtained by the camera is displayed on the display device,thereby increasing the field of view obtained through the side mirror orthe back mirror. The distance measuring sensor has the function ofmeasuring the distance to another vehicle, and the impact sensor has thefunction of sensing an externally applied impact force larger than apredetermined value. Information read from each sensor is displayed onthe display device.

An alarm device is also provided which includes an audio device, adisplay device and a control circuit. When the impact sensor outputs adanger signal, this signal is supplied to a CPU provided in the vehicle.The CPU supplied with the danger signal outputs a signal for indicationof a danger to the display device and a signal for warning of the dangerto the audio device. The display device gives an indication of thedanger and the audio device gives a warning of the danger. Thus, thedriver and the fellow passenger can be warned of the danger.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a vehicle of the present invention;

FIG. 2 is a front view of the vehicle shown of the present invention;

FIG. 3 is a rear view of the vehicle shown of the present invention;

FIGS. 4A, 4B, and 4C are diagrams showing an example of a back mirrorused in the vehicle in accordance with the present invention;

FIGS. 5A, 5B, and 5C are diagrams showing an example of a side mirrorused in the vehicle in accordance with the present invention;

FIG. 6 is a block diagram of the system of the vehicle of the presentinvention;

FIG. 7 is a flowchart of a process using an impact sensor of the presentinvention;

FIG. 8 is a flowchart of a process using a distance measuring sensor ofthe present invention;

FIGS. 9A, 9B, and 9C are diagrams showing a display device used inaccordance with the present invention;

FIG. 10 is a cross-sectional view of an active-matrix liquid crystaldisplay device of Embodiment 1;

FIG. 11 is a top view of the active-matrix liquid crystal display deviceof Embodiment 1;

FIGS. 12A and 12B are block diagrams of drive circuits of theactive-matrix liquid crystal display devices of Embodiment 1;

FIGS. 13A and 13B are a top view and a cross-sectional view,respectively, of the active-matrix liquid crystal display device ofEmbodiment 2;

FIG. 14 is a cross-sectional view of an EL display device of Embodiment3;

FIGS. 15A and 15B are a top view and a cross-sectional view,respectively, of the EL display device of Embodiment 3;

FIGS. 16A, 16B, 16C, and 16D are diagrams showing an example of the backmirror of the vehicle in accordance with Embodiment 4;

FIGS. 17A and 17B are diagrams showing an example of the back mirror ofthe vehicle in accordance with Embodiment 4;

FIGS. 18A, 18B, 18C, and 18D are diagrams showing examples of vehiclesto which the present invention can be applied of Embodiment 6; and

FIG. 19 is a diagram showing a display device provided in an interiorportion of the vehicle of Embodiment 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment Mode

The term “vehicle” used in this specification refers to an electrictrain, a motor vehicle (e.g. car) or the like for conveyance of peopleand goods. A vehicle to which the present invention is applied has anenergy source and a prime mover. The energy source is, for example,electricity or gasoline. The prime mover is a means for supplyingnecessary power for running of the vehicle, which is called an engine.The vehicle also has a body, a transmission, a braking system, asteering mechanism, a suspension, auxiliary equipment, and accessoriesin addition to the energy source and the prime mover.

FIG. 1 is a top view of the vehicle. The vehicle illustrated in FIG. 1is a motor vehicle (car). The vehicle travels forward and backward byusing wheels. In this specification, a portion of the vehicle includingone end of the vehicle in the forward traveling direction will bereferred to as a front portion, and a portion of the vehicle includingthe other end will be referred to as a rear portion. The vehicleillustrated in FIG. 1 uses four wheels 106 for traveling. Two of thewheels 106 are provided in the front portion and the other two areprovided in the rear portion. The vehicle also has four lights 107,i.e., two pairs of lights respectively provided on the front and rearportions. The lights 107 are used during running in the night, in a darktunnel, or in other like situations.

Charge-coupled device (CCD) cameras are used in the vehicle illustratedin FIG. 1. A CCD camera provided on the left-hand side of the frontportion with respect to the vehicle traveling direction will be referredto as a CCD left front (CLF) 100; a CCD camera on the right-hand side ofthe front portion, as a CCD right front (CRF) 101; a CCD camera on theleft-hand side of the rear portion, as a CCD left rear (CLR) 102; and aCCD camera on the right-hand side of the rear portion, as a CCD rightrear (CRR) 103.

In this embodiment mode, a camera of a so-called fisheye structurecapable of image pickup in all directions through 360° is used as eachof the CCD cameras CLF 100, CRF 101, CLR 102, and CRR 103 shown inFIG. 1. In this embodiment, two pair of these CCD cameras arerespectively mounted on the front and rear portions of the vehicle andused to image objects surrounding the vehicle. The number of cameras andthe placement of cameras are not limited to those described above. Forexample, a camera may be mounted on the roof of the vehicle. While thecameras used in this embodiment are CCD cameras, any other type ofcameras may alternatively be used in the present invention as long asthe cameras are capable of image pickup.

The vehicle is provided with two side mirrors. The side mirror on theleft-hand side will be referred to as a display left (DL) 104 and theside mirror on the right-hand side will be referred to as a displayright (DR) 105. The side mirrors are mounted on the opposite sides ofthe body of the vehicle at positions indicated in FIG. 1, for example.Each of the DL 104 and the DL 105 has a display device which is atransmission-type liquid crystal display device, a reflection-typeliquid crystal display device, or an electroluminescent (EL) displaydevice.

FIG. 2 shows a front view of the vehicle shown in FIG. 1. The DL 104 isprovided on the left-hand side of the vehicle and the DR 105 is providedon the right-hand side of the vehicle. The lights 107, the wheels 106,the wipers 114, an antenna 116 are also provided.

The vehicle has a microphone 111 and a sensor 112 mounted on each sideof the vehicle as shown in FIG. 2, although they are not shown inFIG. 1. The vehicle also has a back mirror (room mirror) mounted in theinterior of the vehicle in such a position as to be superposed on awindshield 115 as viewed in FIG. 2. In this specification, the backmirror (room mirror) will be referred to as a back display (BD) 110. TheBD 110 is mounted in or adjacent to a space containing the driver's seatin a place shown in FIG. 2, for example. The BD 110 is provided with adisplay device which is a transmission-type liquid crystal displaydevice, a reflection-type liquid crystal display device, or anelectroluminescent (EL) display device.

FIG. 3 shows a rear view of the vehicle shown in FIG. 1. The vehicle haslights 107 and wheels 106. The vehicle also has CLR 102 mounted on theleft-hand side, CRR 103 mounted on the right-hand side, and themicrophone 111 and the sensor 112 mounted on each side of the vehicle.

FIGS. 4A, 4B, and 4C are enlarged views of the BD 110 shown in FIG. 2,i.e., the back mirror (room mirror) provided in the interior of thevehicle. The BD 110 has a frame 200, a display device 201, and aconnecting portion 202. The frame 200 is made of a material havingsufficiently high strength and easily workable, e.g., a plastic. A drivecircuit, wiring, etc., for the display device 201 are provided in anupper portion of the frame 200 and are connected to a central processingunit (CPU) or the like through the connecting portion 202. Theconnecting portion 202 is capable of protection of the wiring of thedisplay device 201 connected to the CPU or the like.

FIG. 4A shows a state where no image is displayed on the display device201. FIG. 4B shows a state where an image formed by the CCD camera isdisplayed on the display device 201. In the state shown in FIG. 4B, adate and a time are displayed by being superposed on the image.Information such as a date and a time can be displayed when necessaryfor a driver or a fellow passenger.

FIG. 4C shows a state of the BD 110 without the frame 200, and shows apixel portion 206, a source signal line drive circuit 204, a gate signalline drive circuit 205, an external input terminal to which a flexibleprinted circuit (FPC) 203 is attached, and wiring 207 for connecting theexternal input terminal and input portions of the circuits. The FPC 203is connected to a CPU or the like through the connecting portion 202.

FIGS. 5A, 5B, and 5C are enlarged views of the side mirror DR 105mounted on the right-hand side of the vehicle as viewed in FIG. 1. Theside mirror DR 104 mounted on the left-hand side of the vehicle has ashape formed by horizontally flipping the shape of the side mirror DR105. The DR 105 has a display device 211, a frame 210, and a connectingportion 212. The frame 210 is made of a material having sufficientlyhigh strength and easily workable, e.g., a plastic. A drive circuit,wiring, etc., for the display device 211 are provided in a lower portionof the frame 210.

FIG. 5A shows a state where no image is displayed on the display device211. FIG. 5B shows a state where an image formed by the CCD camera isdisplayed on the display device 211. In the state shown in FIG. 5B, adate and a time are displayed by being superposed on the image.Information such as a date and a time can be displayed when necessaryfor a driver or a fellow passenger.

FIG. 5C shows a state of the DR 105 without the frame 210, and shows thepixel portion 206, the source signal line drive circuit 204, the gatesignal line drive circuit 205, the external input terminal to which theflexible printed circuit (FPC) 203 is attached, and wiring 206 forconnecting the external input terminal and input portions of thecircuits. The FPC 203 is connected to the CPU through the connectingportion 212.

It is necessary that the display device in accordance with the presentinvention be formed in such a shape as to be capable of beingaccommodated in the side mirror or back mirror. FIGS. 4C and 5Cillustrate only examples of the shape of the display device. The displaydevice may have any shape if it can be accommodated in the frame.Further, FIGS. 4A-4C and 5A-5C respectively illustrate only examples ofthe shapes of the back mirror and the side mirror, and each of the backmirror and the side mirror may have any other shape.

FIG. 6 is a block diagram showing the structure of the vehicle and thedisplay device used in the present invention.

A CPU 301 has an operating button interface section 302 a and a videosignal processing section 303. The system illustrated in FIG. 6 isconfigured so as to be centrally controlled by the CPU 301. Arrows inFIG. 6 indicate signal inputs and outputs.

Operating buttons 302 c are provided in the interior of the vehicle insuch a position that a user can easily operate it, for example, in aposition closer to the driver's seat. When the operating buttons 302 care operated, a signal from the operating buttons 302 c is input to theoperating button interface section 302 a through a button input signalprocessing circuit 302 b. The input signal undergoes processing in theCPU 301 and predetermined signals are thereby output from the CPU 301 todevices such as an audio processing circuit 305 and a control circuit309 or to a sensor 319.

An audio device 304 has the audio processing circuit 305, a microphone306, and a speaker 307. The microphone 306 is provided outside thevehicle while the speaker 307 is provided in the interior of thevehicle. The microphone 306 converts sound (sound waves) fromsurroundings of the vehicle into an electrical signal and outputs thesignal to the audio processing circuit 305. The audio processing circuit305 outputs a vibrating signal to the speaker 307 to cause mechanicalvibration in a diaphragm of the speaker 307, thereby producing sound(sound waves). The user can operate the audio device 304 through the CPU301 by operating the operating buttons 302 c. That is, the user can hearsounds from surroundings of the vehicle through the audio device 304when necessary.

One or a plurality of cameras 315 are provided in one or a plurality ofplaces in a vehicle 336 and are connected to the CPU 301 through aninterface port 314. The user can operate each camera 315 by operatingthe operating buttons 302 c when necessary. Information from the camera315 is input to the CPU 301 through the interface port 314. Dataprocessing is performed in the CPU 301 to display given information onthe display device 308 through the control circuit 309. Morespecifically, information processed in the CPU 301 is output as a videosignal (data signal) from the video signal processing section 303 to thecontrol circuit 309. The control circuit 309 supplies the video signaland a clock signal (timing signal) to the display device 308. That is,the control circuit 309 has the function of dividing the video signalinto data in correspondence with pixels of the display device 308, andthe function of converting externally-input horizontal and verticalsynchronizing signals into a signal for starting the drive circuit, asignal for controlling timing of forming alternating current in aninternal power supply circuit, and a clock signal.

To the CPU 301 are also connected a video random access memory (VRAM)313, a dynamic random access memory (DRAM) 311, a flash memory 312, anda memory card 310. The CPU 301 is provided in the vehicle 336 andaccommodated in a sturdy heat-resistant box. It is preferred that theCPU 301 be mounted in a place in the vehicle where variation intemperature is comparatively small, such as the lower portion of thedriver's seat.

The sensors 319 comprise an impact sensor 316 and a distance measuringsensor 317. The user can operate the impact sensor 316 and the distancemeasuring sensor 317 through the CPU 301 by the operating buttons 302 c.

The impact sensor 316 will be described with reference to FIG. 7. One ora plurality of impact sensors 316 are provided in one or a plurality ofplaces in the vehicle 336. Each impact sensor 316 senses anexternally-applied impact force larger than a predetermined value andoutputs a danger signal (impact signal) to the CPU 301 when detectingsuch a force.

In FIG. 7, S1 to S3 represent lapses of time, and arrows representsignal inputs and outputs. When the impact sensor 316 senses an impactforce (S1), a danger signal (impact signal) is output from the sensor tothe CPU 301. In the CPU 301 operating for centralized control of thesystem in the vehicle 336, data processing is performed when the CPU 301is supplied with the danger signal (S2). The CPU 301 then outputs asignal to the audio processing circuit 305 in the audio device 304 towarn a driver driving the vehicle or a fellow passenger of a danger by asound through the speaker 307. The CPU 301 also outputs a signal to thecontrol circuit 309 to display a warning about the danger on the displaydevice 308 (S3). In this specification, the combination of the controlcircuit 309 which outputs signals to the display device 308 and thedisplay device 308 which displays a warning about a danger will bereferred to as an alarm device 340.

The distance measuring sensor 317 will next be described with referenceto FIG. 8. One or a plurality of distance measuring sensors 317 areprovided in one or a plurality of places in the body of the vehicle.Each distance measuring sensor 3 17 is used to measure the distance toanother vehicle existing on the front, rear, left-hand or right-handside of the vehicle having the sensor. The user can use the distancemeasuring sensor 317 by operating the operating buttons 302 c whennecessary.

Referring to FIG. 8, a light emitting portion 401 is that of ascanning-type laser. The scanning-type laser moves in a scanning mannera laser beam in synchronization with an output signal produced in alight emitting signal output section 403. The laser beam emitted fromone of the distance measuring sensors 317 provided in suitable portionsof the vehicle is reflected by some other vehicle and received through alight receiving portion 402. The received laser beam is supplied to adistance computation section 405 through a received light signaldetection section 404. In the distance computation section 405, thedistance between the vehicles is computed from the time from the momentat which the laser beam is emitted to the moment at which the laser beamis returned by being reflected.

Information on the distance between the vehicles computed in thedistance computation section 405 is output to the CPU 301 through adistance indication output section 406. In the CPU 301, data processingof the supplied information is performed. A signal is output from theCPU 301 to the control circuit 309 to indicate on the display device 308the distance between the vehicles computed in the distance computationsection 405. The CPU 301 is connected to the operating buttons 302 c toenable the user to display the information read with the distancemeasuring sensor 317 on the display device 308 by operating theoperating buttons 302 c when necessary.

In this embodiment, a scanning-type laser is used as the light emittingportion 401. However, the present invention is not limited to this, andany other type of laser may alternatively be used.

FIGS. 9A, 9B, and 9C are diagrams each showing an example of display ofinformation read from the impact sensor 316 and the distance measuringsensor 317, the information being displayed on the display deviceprovided in the back mirror BD 110.

FIG. 9A shows a state of display of an image from one of the camerasmounted on the vehicle. FIG. 9B shows a state where a date, a time, thedistance to a vehicle in front and the distance to a vehicle in back aredisplayed in addition of an image from the camera mounted on thevehicle. FIG. 9C shows a state where an image from the camera mounted onthe vehicle and a warning given when the impact sensor outputs adetection signal are displayed on the display device.

As described above, information read from the camera, distance measuringsensor and impact sensor mounted on the vehicle is displayed on each ofthe display devices provided in the side mirror and the back mirror whennecessary, thus enabling a driver driving the vehicle or a fellowpassenger to obtain necessary information.

Embodiment 1

A liquid crystal display device which is an example of the displaydevice provided in the side or back mirror and which represents anembodiment of the present invention will be described.

FIG. 10 shows an example of a liquid crystal display device having apixel portion 602 and a drive circuit 601 for driving the pixel portion602 (in a state before a liquid crystal material is contained).

A complementary metal-oxide-silicon (CMOS) circuit, which is a basicunit of the drive circuit 601, and one pixel in the pixel portion 602are illustrated.

Referring to FIG. 10, on a substrate are formed the drive circuit 601including a logic circuit 680 and a sampling circuit 681, which areconstituted by n-channel thin-film transistors (TFTs) 605 and 606 andp-channel TFTs 603 and 604, and the pixel portion 602 constituted by apixel TFT 607, which is an n-channel TFT, and a storage capacitor 608.In this embodiment, each TFT is formed as a top gate type of TFT.

The pixel TFT 607 has a structure (double-gate structure) in which twochannel forming regions are provided between a source region and a drainregion. In this embodiment, however, the double-gate structure is notexclusively used and a single-gate structure in which one channelforming region is formed or a triple-gate structure in which threechannel-forming regions are formed may alternatively be used.

In this embodiment, a pixel electrode connected to the drain region ofthe pixel TFT 607 is formed as a reflecting electrode. Preferably, thepixel electrode is formed of a member having high reflectivity, e.g., afilm of a material having Al or Ag as a main component of laminatedfilms of such materials. Preferably, the formed pixel electrode isprocessed by an additional well-known sandblasting or etching step toform irregularities in its surface, thereby preventing mirror reflectionand scattering reflected light so that the whiteness level is increased.

While the embodiment has been described as a reflection type of liquidcrystal display device having the pixel electrode formed as a reflectingelectrode, a transmission type of liquid crystal display device mayalternatively be used in which the pixel electrode is formed as atransparent electroconductive film instead of the reflecting electrode.

After the progression of the fabrication process to the state shown inFIG. 10, an alignment film is formed over the pixel electrode andundergoes rubbing. In this embodiment, pillar-like spacers for setting asubstrate spacing are formed at predetermined positions by patterning anorganic resin film such as an acrylic resin film before the formation ofthe alignment film. Spherical spacers may be provided by being dispersedover the entire substrate surface instead of the pillar-like spacers.

Next, an opposed substrate is prepared. A colored layer and a lightshielding layer are formed on the opposed substrate. A leveling film isthereafter formed. Next, a counter electrode formed of a transparentconductive film is formed on the leveling film at least above the pixelportion 602, and an alignment film is formed on the entire surface ofthe opposed substrate and rubbed.

The stainless substrate on which the pixel portion 602 and the drivecircuit 601 are formed and the fixed substrate are attached to eachother by an adhesive layer (a layer of a sealing material in thisembodiment). A filler is mixed in the material of the adhesive layer.The two substrates are attached to each other by being uniformly spacedapart from each other by the filler and the pillar-like spacers. The gapbetween the two substrates is thereafter filled with a liquid crystalmaterial and is completely sealed with a sealing material (not shown).The liquid crystal material is not limited to a particular kind andsealing may be made by using any of well-known liquid crystal materials.

After the step of filling the gap with the liquid crystal and sealingthe gap (or containing the liquid crystal), the substrate holder isseparated. A state of the above-described liquid crystal display deviceafter this step, represented by a state shown in FIG. 11, will next bedescribed.

In the state illustrated in the top view of FIG. 11, a stainlesssubstrate 619 on which a pixel portion 610, a drive circuit (a gatesignal line drive circuit 613, a source signal line drive circuit 614),an external input terminal to which an FPC 616 is attached, wiring 618for connecting the external input terminal and input portions of thecircuit, etc., are formed and an opposed substrate 620 on which a colorfilter 611, etc., are formed are attached to each other by a sealingmaterial 615.

A light shielding layer 612 a is provided on the opposed substrate 620side by being superposed on the gate signal line drive circuit 613, anda light shielding layer 612 b is also provided on the opposed substrate620 side by being superposed on the source signal line drive circuit614. The color filter 611 provided on the opposed substrate 620 side ofthe pixel portion 610 has colored layers having colors red (R), green(G), and blue (B) formed in correspondence with pixels. In actual colordisplay, a multicolor image is displayed by using the three colors ofthe red (R) colored layer, the green (G) colored layer and the blue (B)colored layer. The colored layers having these colors may be arrayed inany pattern.

The color filter 611 for colorization is not necessarily provided on theopposed substrate 620. It may be formed on the stainless substrate 619at the time of device fabrication on the stainless substrate 619.

A light shielding layer is provided between adjacent pixels in the colorfilter 611 to block light at portions other than the display region. Inthis embodiment, the light shielding layers 612 a and 612 b are alsoprovided on the regions covering the drive circuit (the gate signal linedrive circuit 613, the source signal line drive circuit 614). However,the liquid crystal display device may be formed without light shieldinglayers 612 a and 612 b because the regions covering the drive circuit(the gate signal line drive circuit 613, the source signal line drivecircuit 614) are covered with portions of an electronic device when theliquid crystal display device is incorporated as a display unit in theelectronic device. Alternatively, light shielding layers may be formedon the stainless substrate 619 when the necessary elements arefabricated on stainless substrate 619.

Further, the arrangement may alternatively be such that theabove-described light shielding layers 612 a and 612 b are not providedbut a plurality of colored layers constituting the color filter arelaminated at suitable positions between the opposed substrate 620 andthe counter electrode to block light at portions (the gaps between thepixel electrodes) other than the display region and at the drive circuit(the gate signal line drive circuit 613, the source signal line drivecircuit 614).

The FPC 616 formed of a base film and wiring is attached to the externalinput terminal by an anisotropic electroconductive resin. Thisconnection is mechanically reinforced by a reinforcing plate.

A polarizing plate (not shown) is attached only to the opposed substrate620.

The liquid crystal display device fabricated as described above can beused as a display device mounted in the side or back mirror.

Examples of a circuit configuration in the liquid crystal display devicein this embodiment will next be described with reference to FIGS. 12Aand 12B.

FIG. 12A shows a circuit configuration for analog drive having a sourceline drive circuit 631, a pixel portion 630, and a gate line drivecircuit 632.

The source line drive circuit 631 has a shift register 631 a, a buffer631 b, a sampling circuit (transfer gate) 631 c. The gate line drivecircuit 632 has a shift register 632 a, a level shifter 632 b, and abuffer 632 c. A level shifter circuit may be provided between thesampling circuit and the shift register if necessary.

In this embodiment, the pixel portion 630 includes a plurality of pixelseach having a TFT device.

All TFT devices provided in the source line drive circuit 631 and thegate line drive circuit 632 may be formed as p-channel TFTs or n-channelTFTs, or may be formed by using a combination of p-channel TFTs andn-channel TFTs.

Another gate line drive circuit (not shown) may also be provided on theside of the pixel portion 630 remote from the gate line drive circuit632.

If digital drive is performed, latches (A) 634 b and 634 c may beprovided instead of the sampling circuit, as shown in FIG. 12B. A sourceline drive circuit 634 has a shift register 634 a, a latch (A) 634 b, alatch (B) 634 c, a D/A converter 634 d, and a buffer 634 e. A gate linedrive circuit 635 has a shift register 635 a, a level shifter 635 b, anda buffer 635 c. A level shifter circuit may be provided between thelatch (B) 634 c and the D/A converter 634 d.

Although only the configurations of the pixel portion and the drivecircuit have been described with respect to this embodiment, a memoryand a microprocessor may also be formed.

This embodiment may be arranged in combination with any of theabove-described features in the mode of implementation of the invention.

Embodiment 2

A second embodiment of the present invention in which each of TFTs usedin the pixel portion and the drive circuit of a liquid crystal displaydevice provided as a display device mounted in the side or back mirroris formed as an inverted stagger type of TFT will be described withreference to FIGS. 13A and 13B. FIG. 13A is an enlarged top view of oneof pixels in the pixel portion. A portion taken along a dotted line A-A′in FIG. 13A corresponds to the sectional view of the structure of thepixel portion in FIG. 13B. A member 651 illustrated in FIG. 13B is asubstrate having an insulating surface.

In the pixel portion, each of pixel TFTs 690 is formed as an n-channelTFT. A gate electrode 652 is formed on the substrate 651. A firstinsulating film 653 a formed of silicon nitride and a second insulatingfilm 653 b formed of silicon oxide are formed on the gate electrode 652and the substrate 651. On the second insulating film 653 b are formed,as regions in an active layer, n⁺ regions 654 to 656, channel formingregions 657 and 658, and n regions 659 and 660. The n regions 659 and660 are formed among the n⁺ regions 654 to 656 and the channel formingregions 657 and 658. The channel forming regions 657 and 658 areprotected by insulating layers 661 and 662. Contact holes are formed ina first interlayer insulating film 663 with which the insulating layers661 and 662 and the active layer are covered. After the formation of thecontact holes, wiring 664 connected to the n⁺ region 654 is formed, apixel electrode 665 made of Al or Ag is connected to the n⁺ region 656,and a passivation film 666 is formed thereon. Reference numeral 670 is apixel electrode adjacent to the pixel electrode 669.

In this embodiment, the gate wiring to the pixel TFT in the pixelportion is formed in the double-gate structure. However, a multigatestructure such as a triple-gate structure may alternatively be used inorder to reduce variation in off current. Further, a single gatestructure may be used to increase the aperture ratio.

The capacitor portion 691 in the pixel portion is formed by capacitorwiring 671 and the n⁺ region 656 with the first insulating film 653 aand the second insulating film 653 b used as a dielectric.

The pixel portion shown in FIGS. 13A and 13B is only an example and thepresent invention is not limited to the above-described arrangement.

The liquid crystal display device fabricated as described above can beused as a display device mounted in the side or back mirror inaccordance with the present invention.

This embodiment may be arranged in combination with any of theabove-described features of Embodiment 1.

Embodiment 3

A third embodiment of the present invention in which anelectroluminescent (EL) display device is provided as a display devicemounted in the side or back mirror of a vehicle will be described.

FIG. 14 shows an example of a light emitting device in which a pixelportion 705 and a drive circuit 704 for driving the pixel portion 705are provided on one substrate (and which is in a state before sealing).A CMOS circuit which is a basic unit in the drive circuit 704 isillustrated.

Referring to FIG. 14, a member 701 is a substrate on which an insulatingfilm is formed. The CMOS of the drive circuit 704 constituted by ann-channel TFT 720 and a p-channel TFT 721 is formed on the insulatingfilm. A switching TFT 702, which is a p-channel TFT, and a currentcontrol TFT 703, which is an n-channel TFT, are also formed on theinsulating film. In this embodiment, each TFT is formed as a top gatetype of TFT. However, the present invention is not limited to this.

The switching TFT 702 has a structure (double-gate structure) in whichtwo channel forming regions are provided between a source region and adrain region. In this embodiment, however, the double-gate structure isnot exclusively used and a single-gate structure in which one channelforming region is formed or a triple-gate structure in which threechannel-forming regions are formed may alternatively be used.

A contact hole is formed in a first interlayer insulating film 707 abovea drain region 706 of the current control TFT 703 before a secondinterlayer insulating film 708 is formed. This procedure is adopted tosimplify an etching process when a contact hole is formed in the secondinterlayer insulating film 708. The contact hole is formed in a secondinterlayer insulating film 708 so as to extend to the drain region 706,and a pixel electrode 709 is formed so as to connect to the drain region706 of the current control TFT 703. The pixel electrode 709 is anelectrode which functions as a cathode of an EL element 710, and whichis formed by using a conductive film containing an element which belongsto the group 1 or 2 in the periodic table. In this embodiment, aconductive film formed of a compound of lithium and aluminum.

An insulating film 713 is formed so as to cover an end portion of thepixel electrode 709. The insulating film 713 will be referred to as“bank” in this specification. The bank 713 may be formed of aninsulating film containing silicon or a resin film. If a resin film isused, carbon particles or metal particles may be added so that theresistivity of the resin film is 1×10⁶ to 1×10¹² Ωm (preferably 1×10⁸ to1×10¹⁰ Ωm), thereby reducing the possibility of insulation breakdown atthe time of film forming.

The EL element 710 is constituted by the pixel electrode (cathode) 709,an EL layer 711, and an anode 712. To form the anode 712, a conductivefilm having a high work function, typically an oxide conductive film isused. As an oxide conductive film, indium oxide, tin oxide, zinc oxideor a component of such oxides may be used. The light emitting device inthis embodiment is formed as an upward emission type of light emittingdevice. However, this embodiment is not limited to the upward emissiontype of light emitting device, and a downward emission type of lightemitting device can be formed by suitably changing the structure of theEL element.

In this embodiment, an EL layer 711 is defined as a laminated memberhaving a combination of a light emitting layer and a hole injectionlayer, a hole transport layer, hole block layer, an electron transportlayer, an electron injection layer or an electron block layer.

Any of well-known EL materials may be used to form the light emittinglayer. For example, a thin film of a light emitting material capable ofemitting light by singlet excitation (singlet compound) or a thin filmof a light emitting material capable of emitting light by tripletexcitation (triplet compound) is used.

A method (not illustrated) may be effectively used in which, after theformation of anode 712, a passivation film is formed so as to completelycover the EL element 710. The passivation film may be an insulating filmcomprising a carbon film, a silicon nitride film or a silicon nitrideoxide film, or may be a single layer of such an insulating film or alayer formed by laminating a combination of such films.

The fabrication process includes, as a final step, the step of sealing(encapsulation) for protection of the EL element are performed. The ELdisplay device after sealing will be described with reference to FIGS.15A and 15B.

FIG. 15A is a top view when the step of sealing the EL element iscompleted, and FIG. 15B is a cross-sectional view taken along line A-A′in FIG. 15A. A region 801 indicated by a dotted line corresponds to apixel portion, a region 802 corresponds to a source line drive circuit,and a region 803 corresponds to a gate line drive circuit. A covermember 804, a first sealing material 805, and a second sealing material806 are provided.

An FPC 808 is a wiring for transmitting signals to be input to thesource line drive circuit 802 and the gate line drive circuit 803. Inother words, the source line drive circuit 802 and the gate line drivecircuit 803 are supplied with a video signal and a clock signal throughthe FPC 808 corresponding to an external input terminal. A printedwiring base (PWB) may be attached to the FPC 808 although only the FPC808 is illustrated.

The structure of the display device will be described with reference tothe cross-sectional view of FIG. 15B. The pixel portion and a sourceline drive circuit 809 are formed above a substrate 800. The pixelportion is formed by a plurality of pixels each including a currentcontrol TFT 810 and a pixel electrode 811 electrically connected to thedrain of the current control TFT 810. The source line drive circuit 809is formed by using a CMOS circuit comprising a combination of n-channelTFTs and p-channel TFTs. A polarizing plate (typically a circularlypolarizing plate) may be attached to the substrate 800.

Banks 812 are formed on opposite ends of the pixel electrode 811, and anEL layer 813 and an anode 814 of the EL element are formed on the pixelelectrode 811. The anode 814 also functions as a common wiring for allthe pixels and is electrically connected to the FPC 816 by connectionwiring 815. All the elements included in the pixel portion and thesource-side drive circuit 809 are covered with a passivation film (notshown).

The cover member 804 is attached by the first sealing material 805.Spacers may be provided for spacing between the cover member 804 and theEL device. A space 817 is formed inside the first sealing material 805.It is preferred that the first sealing material 805 be impermeable towater and oxygen. Further, it is effective to provide in the space 817 amaterial having a hygroscopic effect and/or a material having ananti-oxidizing effect.

Preferably, a carbon film (specifically, a diamond-like carbon film)having a thickness of about 2 to 30 nm may be formed as a protectivefilm on each of the outer and inner surfaces of the cover member 804.Such a carbon film (not shown) has the functions of preventing oxygenand water from entering the display device and mechanically protectingthe surface of the cover member 804.

After bonding of the cover member 804, the second sealing material 806is provided so as to cover the exposed surface of the first sealingmaterial 805 The same material as the first sealing material 805 may beused as second sealing material 806.

The EL device is encapsulated in the above-described structure to becompletely shielded from the outside, thereby preventing substances suchwater and oxygen capable of degrading the EL layer by oxidation fromentering the device. Thus, an EL display device having improvedreliability can be obtained.

The EL display device fabricated as described above can be used as adisplay device mounted in the side or back mirror in accordance with thepresent invention. This embodiment may be arranged in combination withany of the above-described features of Embodiments 1 and 2.

Embodiment 4

An embodiment of the present invention represented by a back mirror or aside mirror of a construction different from that in the above-describedmode of implementation of the invention will be described with referenceto FIGS. 16A-16D and 17A-17B. FIGS. 16A-16D and 17A-17B show examples ofthe back mirror BD 110.

FIGS. 16A to 16D are enlarged diagram of the back mirror BD 110 mountedon the vehicle shown in FIG. 2. FIG. 16A shows a mirror 220, and FIG.16B shows the display device 201. FIG. 16C shows the frame 200. Theframe 200 is made of a material such as a plastic easily workable andhas a cavity.

FIG. 16D is a cross-sectional view seen along a lengthwise direction ofthe back mirror BD 110. The mirror 220 and the display device 201 areplaced in the frame 200, the mirror being superposed on the displaydevice and positioned externally relative to the display device. The FPC203 of the display device 201 is connected via the connecting portion202 to the CPU provided in the vehicle.

The mirror 220 is a mirror called a one-way mirror or half mirror, i.e.,a mirror having a glass plate on which a thin film of a metal is formedand another glass plate superposed on the metal film. That is, an objecton the light side can be seen through the mirror from the dark side,while no object at the back of the mirror can be seen through the mirrorfrom the light side. That is, when the display device 201 is notactivated, the BD 110 functions as a mirror. When the display device 201is activated, a user can recognize a display on the display device 201through the mirror 220.

Other examples of the back mirror BD 110 each different in constructionfrom that shown in FIGS. 16A to 16D will be described with reference toFIGS. 17A and 17B.

The size of the BD 110 shown in FIG. 17A is about twice that of the BD110 shown in FIG. 16C. While the mirror 220 and the display device 201are superposed in the arrangement shown in FIGS. 16A to 16D, the displaydevice 201 shown in FIG. 17A is placed parallel to the mirror 220.

The size of the BD 110 is not specially limited and may be freelyselected in designing by a designer.

The size of the BD 110 shown in FIG. 17B is approximately the same asthat of the BD 110 shown in FIG. 16C. In the arrangement shown in FIG.17B, however, the display device 201 and the mirror 220 eachapproximately half the size of the display device or mirror shown inFIG. 16C or 16A are placed parallel in a side by side fashion. Themirrors shown in FIGS. 17A and 17B may be of any type not limited to thehalf mirror in the arrangement shown in FIGS. 16A to 16D as long as theyfunction as a mirror.

This embodiment may be arranged in combination with any of theabove-described features of Embodiments 1 to 3.

Embodiment 5

An example of provision of the display device in the back or side mirrorhas been described with respect to the mode of implementation. Anembodiment of the present invention in which the display device isprovided in an interior portion of the vehicle will be described withreference to FIG. 19.

FIG. 19 shows the interior of a vehicle in the vicinity of the driver'sseat and the fellow passenger's seat. A steeling wheel 901, operatingbuttons 902, a display device 903, and a speaker 904 are illustrated inFIG. 19 by way of example. A driver who drives the vehicle operates thesteeling wheel 901. A user uses the operating buttons 902 when operatinga sensor or a camera. The speaker 904 can be used as an audio device.

Information read from the camera and sensor is displayed on the displaydevice 903 to enable the driver and the fellow passenger in the vehicleto obtain necessary information.

The display device shown in FIG. 19 is placed in the vicinity of thedriver's seat. However, the present invention is not limited to this.For example, the display device may be provided on the driver's seat orthe fellow passenger's seat to be easily viewed by a passenger sittingin a rear seat. The placement of the operating buttons 902 and that ofthe speaker 904 in this embodiment are only an example and the operatingbuttons 902 and the speaker 904 may be mounted in any other places inthe vehicle. The operating buttons 902 may be provided in a remotecontroller.

This embodiment may be arranged in combination with any of theabove-described features of Embodiments 1 to 4.

Embodiment 6

The display device of the present invention is used for variouspurposes. An embodiment of the present invention relating applicationsof vehicles in which the display device of the present invention isincorporated will be described with reference to FIGS. 18A to 18D.

The mode of implementation of the invention has been described withrespect to a vehicle for transport of a small number of passengers byway of example. However, vehicles to which the present invention can beapplied include motor vehicles, such as sport cars, trucks, buses,station wagons, special-purpose vehicles (ambulance cars, etc.),special-type vehicles (tractors, etc.), specially-equipped vehicles(tank trucks, etc.), electric train, cars, and motorcycles. FIGS. 18A to18D show examples of such vehicles.

FIG. 18A illustrates a bus for transport of a large number ofpassengers. The bus has a side mirror 2001, a back mirror 2000, a camera2002, a sensor 2003, and lights 2004. The bus also has wheels 2005 andtravels on a road by the wheels 2005. The display device of the presentinvention can be mounted in each of the side mirror 2001 and the backmirror 2000.

FIG. 18B illustrates a sport car for enjoying sport driving. Thepassenger capacity of the sport car is ordinary two and at most four.The sport car has a back mirror 2010, a side mirror 2011, a camera 2012,a sensor 2013, and lights 2014. The sport car also has wheels 2015 anduses the wheels 2015 when traveling on a road. The display device of thepresent invention can be mounted in each of the back mirror 2010 and theside mirror 2011.

FIG. 18C illustrates an electric train car having a side mirror 2021, acamera 2022, a sensor 2023, and lights 2024. The car also has wheels2025 and uses the wheels 2025 when traveling on rails. The displaydevice of the present invention can be mounted in the side mirror 2021.

FIG. 18D illustrates a motorcycle having a side mirror 2031, a camera2032, a sensor 2033, and a light 2034. The motorcycle also has wheels2035 and uses the wheels 2025 when traveling on a road. The displaydevice of the present invention can be mounted in the side mirror 2031.

As described above, the range of application of the present invention ismarkedly wide and the invention can be applied to all kinds of vehicles.Further, this embodiment may be arranged in combination with any of theabove-described features of Embodiments 1 to 5.

According to the present invention, the display device is mounted in aside mirror (door mirror) and a back mirror (room mirror) provided on avehicle, or in an interior portion of the vehicle. The display devicedisplays an image of any of objects surrounding the vehicle, which isobtained by a camera provided on the vehicle. The field of view obtainedthrough the side or back mirror can be increased thereby. Also,information obtained through the sensor mounted on the vehicle isdisplayed on the display device, and the user of the display device candisplay the information according to user's need.

The vehicle in accordance with the present invention is provided with analarm device which is constituted by an audio device and a displaydevice. When an impact sensor outputs a danger signal, an indication ofa danger is provided on the display device and a warning of the dangeris given through the audio device.

As described above, the display device is provided in side and backmirrors or in an interior portion of a vehicle to enable a driver and afellow passenger to obtain necessary information at any time.

1. A vehicle comprising: a mirror; a camera; and a display devicemounted in the mirror, the display device comprising: a substrate, afirst thin film transistor formed over the substrate, a pixel electrodeelectrically connected to the first thin film transistor, a lightemitting layer adjacent to the pixel electrode, a second electrodeadjacent to the light emitting layer wherein the light emitting layer isdisposed between the pixel electrode and the second electrode, and acover member covering the second electrode and fixed to the substrate bya sealing material, wherein the display device is configured to displayinformation read from the camera, and wherein the display device isconfigured to emit light from the light emitting layer through the covermember.
 2. A vehicle according to claim 1 wherein the camera comprises aCCD camera.
 3. A vehicle according to claim 1 wherein the mirror is aside mirror.
 4. A vehicle according to claim 1 wherein the mirror is aback mirror.
 5. A vehicle according to claim 1 further comprising adriver circuit comprising a second thin film transistor formed over thesubstrate and operationally connected to the first thin film transistor.6. A vehicle according to claim 1 further comprising a centralprocessing unit and a video signal processing section in the centralprocessing unit, said video signal processing section being configuredto be supplied with information read by the camera.
 7. A vehicleaccording to claim 1 wherein the second electrode is an anode.
 8. Avehicle comprising: a mirror; a sensor for measuring a distance toanother vehicle; and a display device mounted in the mirror, the displaydevice being configured to display information read from the sensor,wherein the display device comprises: a substrate, a first thin filmtransistor formed over the substrate, a pixel electrode electricallyconnected to the first thin film transistor, a light emitting layeradjacent to the pixel electrode, a second electrode adjacent to thelight emitting layer wherein the light emitting layer is disposedbetween the pixel electrode and the second electrode, and a cover membercovering the second electrode and fixed to the substrate by a sealingmaterial; and wherein the display device is configured to emit lightfrom the light emitting layer through the cover member.
 9. A vehicleaccording to claim 8 wherein the mirror is a side mirror.
 10. A vehicleaccording to claim 8 wherein the mirror is a back mirror.
 11. A vehicleaccording to claim 8 further comprising a driver circuit comprising asecond thin film transistor formed over the substrate and operationallyconnected to the first thin film transistor.
 12. A vehicle according toclaim 8 further comprising a central processing unit and a video signalprocessing section in the central processing unit, said video signalprocessing section being configured to be supplied with information readby the sensor.
 13. A vehicle according to claim 8 wherein the secondelectrode is an anode.
 14. A vehicle comprising: a mirror; a sensor forsensing an impact; and a display device mounted in the mirror, thedisplay device being configured to display information read from thesensor, wherein the display device comprises: a substrate, a first thinfilm transistor formed over the substrate, a pixel electrodeelectrically connected to the first thin film transistor, a lightemitting layer adjacent to the pixel electrode, a second electrodeadjacent to the light emitting layer wherein the light emitting layer isdisposed between the pixel electrode and the second electrode, and acover member covering the second electrode and fixed to the substrate bya sealing material; and wherein the display device is configured to emitlight from the light emitting layer through the cover member.
 15. Avehicle according to claim 14 wherein the mirror is a side mirror.
 16. Avehicle according to claim 14 wherein the mirror is a back mirror.
 17. Avehicle according to claim 14 further comprising a driver circuitcomprising a second thin film transistor formed over the substrate andoperationally connected to the first thin film transistor.
 18. A vehicleaccording to claim 14 further comprising a central processing unit and avideo signal processing section in the central processing unit, saidvideo signal processing section being configured to be supplied withinformation read by the sensor.
 19. A vehicle according to claim 14wherein the second electrode is an anode.